Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 379

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-379 A Onekama MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348      
231-379 0 Onekama MI GDRPMIBL00Z  991E BANDWIDTH.COM CLEC, LLC - MI 348   2021-10-29   
231-379 1 Onekama MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2023-08-12   
231-379 2 Onekama MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2022-12-29   
231-379 9 Onekama MI BRSPMI09FMD  145J TERRA NOVA TELECOM INC. 348   2024-02-14   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

Sponsored by: Execulink Telecom

Like this site? We accept donations via PayPal.